Coin counting and sorting equipment is often adversely affected by the presence of foreign matter. Mechanical and electronic sorting systems and methods can fail, be damaged, caused to misread and/or become jammed. Mechanical devices such as coin transport mechanisms, coin hoppers and the like may be caused to jam or otherwise malfunction by foreign matter. Sensors may be prevented from accurately identifying a coin because of non-coin matter accompanying the coins. Sensors may become blocked or rendered ineffective because of non-coin matter collecting and or being deposited onto sensor parts. When the sensors fail the coin counting process has failed and coins are often undesirably rejected or are accepted as the incorrect denomination. The amount of non-coin matter varies and is unpredictable. In many situations, the reliability and accuracy of coin sorting, identification and/or counting processes is very important and thus the process of removing non-coin matter before the coins are transported to sorting, identification and/or counting sensors is important. The presence of non-coin matter is believed to be especially troublesome in the context of self-service, stand-alone, unmonitored and/or unattended devices, e.g. devices for counting/sorting coins by the general public or other non-trained persons. Accordingly, it would be useful to provide self-service coin processing machinery which can process coins which are accompanied by non-coin matter.
The removal of one type of undesirable non-coin matter does not often eliminate other kinds because the material is so varied. Metal objects may be identified by properties such as density, shape, magnetic characteristics, etc. Typically, removing dense matter such as rocks is entirely different than removing metal or paper objects. Coins may have been stored with materials that have caused corrosion or have become coated with oils, glue and other liquids that collect dirt and other debris. These coins contaminate others as they come into physical contact and may cause adhesion, clumping or grouping of coins. A magnetic separator would not eliminate all this various non-coin matter.